Material length scale and nonlocal effects on the wave propagation of composite laminated cylindrical micro/nanoshells

Wave propagation in composite laminated cylindrical microshell was investigated by accounting for simultaneous effects of two influential parameters resulting from the nonlocal and strain gradient effects. The thin shell model was used for modeling the composite laminated cylindrical microshell, and the nonlocal strain gradient theory was employed as well. Classical governing equations were derived from Hamilton's principle. The results demonstrate that the rigidity of the composite laminated cylindrical microshell in the strain gradient theory is more than that in the classical theory and less than that in the nonlocal theory. Moreover, the effect of fiber angle in layers on phase velocity of the composite laminated cylindrical microshell was investigated, demonstrating that the size parameter, the composite laminated cylindrical microshell thickness, and the circumferential wave number have considerable effects on the phase velocity of the composite laminated cylindrical microshell.